Slag cement



Patented June 6, 1933 l l i UNITED STATES PATIENT OFFICE No Drawing. Application filed July 22, 1931. Serial No. 552,541.

It is an object of the present invention to of magnesium silicofluoride and 2 parts by i provide a slag cement of this class, in which weight of calcium fluoride.

thebinding qualities will be raised to the 2. A slag cement made up of a finely highest degree, and in which the maximum ground m xture of granulated blast furnace amount of strength may be afforded. slag, calcium hydrox de, sodium hydrate, A th bj t i t id a l g emagneslum silicofluorlde and calcium fiuorment composition which will possess qualiide. ties of water-proofing and strength exceed In testimony whereof, I have hereunto ing those of any known kind of cement, and s g ecl my a e o t s sp c ficatlon.

which will be cheap to manufacture and GEORGE WITTY.

adapted for shipment in a dry powder form to be mixed with water for use. p My invention consists of a mixture of granulated blastfurnace slag, calcium hyl 5 droxide, sodium hydrate or its equivalents, I

magnesium silicofluoride and calcium fluoride. The proportions which I prefer to employ are 100 pounds granulated blastfurnace slag, 30 pounds of calcium hydrox- 2 ide, 2 pounds of magnesium silicofluoride I and 2 pounds of calcium fluoride. These proportions may of course be varied, according to the character of the slag and the quality of cement desired to produce. This composition having been made up is ground in a tube mill or similar apparatus adapted to afford the great fineness and intimacy of the mixture. The resultant product is then placed in bags and ready for use.

The advantages of my invention result from the use of the sodium hydrate, magnesium silicofluoride and calcium fluoride, since they greatly improve the strength, specific gravity, hardness and water-proofing qualities of the cement.

The proportions will naturally be varied according to the composition of the slag used, and the above is given as an example.

40 The setting time of the cement could be varied from fast to slow by varying the proportions of the chemicals.

Having fully described my invention what I claim as new, and desire to secure by l 4 Letters Patent, is:

1. A slag cement including a parts by weight of a finely ground mixture of granulated blast furnace slag, 30 parts by weight of calcium hydroxide, 3 pounds by 9 weight of sodium hydrate, 2 parts by weight 

